1985

7.7

1998

8.3

1961

6.9

2004

5.3

1982

6.6

1987

6.4

1992

5.3

1972

7.5

1992

7.8

2008

7.0

2001

6.1

2007

5.5

1954

7.2

2004

6.4

2002

5.2

1966

7.5

2004

7.0

1999

6.8

1985

5.8

1964

7.4